A NEW LIGHT.

Gisborne Times, Volume V, Issue 138, 21 June 1901, Page 4

A NEW LIGHT.

MARVELLOUS PROPERTY OP RADIUM. To make a lamp that will give light without fuel is the dream of the scientist. To create a substance that will give out radiance with out heat or the consumption of some material has been on the list of impossible, made by everyday practical folk, but the scientist has persisted in dreaming. The realisation of this dream is a great deal nearer than is supposed outside of the great chemical laboratories of the world. - In fact, the chemical has actually been produced. The light is somewhat feeble, it is true, but photographs have actually been made by means of it. From a strictly scientific point of view the discovery is a great deal ne,arcr perfection than the X-ray was only throe years ago. Radium is the name given to the new substance, and the discovery, of it was made by a woman, Mme. Sklowdowska Currie, of the municipal School of Physics in Paris. For this she has been awarded one of the regular prizes of 4000 francs and given a place of honor in the French Academy of Sciences.

The generally accepted idea about the origin of light is that it is merely the demolish atton of an energy produced by the destruction or consumption of certain substances, such as coal, oil, or gas. The discovery of the wonderful properties of the X-ray set men to thinking. It then became apparent that there were more than one form of radiant energy, all of them having the same qualities in certain directions, but entirely different in others. Soientifio students soon found that the metal uranium possessed some of the most remarkable properties in this direction. First it was found to have the power of absorbing light and afterwards emitting it. Then investigations wero followed out by experimenting with different salts of the metal, alone and in combination. The results were surprising. Some substances were produced having properties similar to X-rays. They were invisible to the eye, and yet had the power of “fogging” a photographic plate when brought into contact with it. Different forms of these rays were produced by different investigators, hut all failed of producing anything more promising than a laboratory experiment. They had an energy, but no luminosity, which rendered all iff their work useless as far as the demands of the busy world are concerned.

Where they left off about a year ago, Mme. Currie took up the work. She wisely concluded that the wonderful properties manifo:ted by the different substances obtained from uranium were not due to any real power of the metal itself, but to sonro substance which it held in a state of quietude, or nonaetivity. Following out this theory she began her work with a substance known as “ pitchblend.” Chemically this is uraninite, and is the refuse from the factories where different uranium products are manufactured. The first work done by Mme. Currie was the discovery of a substance similar to bismuth and several thousand times more powerful than the uranium salt from which it was Following along her own lines, Mme. Currie’s efforts were crowned with success about two months ago. By using different salts in combination with the bismuth she produced a substance with some of the properties of barium, but having the power, after being heated, of emitting visible rays of light. This is the substance which she named “radium.”

After the production of the first piece of radium it was only natural to suppose that there might have been some accident that led to its origin instead of thorough scientific manipulation. Investigation, however, showed conclusively the results were sound, and that there was a perfect formula to be followed. Radium could be produced at will. Different tests were made to show the exact nature of the material. Pieces were dropped into gunpowder and a glow spread all through the inflammable material, but there was no explosion. There was no heat and no fireonly light. Everything likely to start combustion was tried, but always resulted in failure. In order to destroy the luminosity of radium it was necessaay to drop it into boiling water and keep it there for an hour. On removal it looked like a piece of green quartz, dead and cold. But on heating the substance to the point of incandescence the luminosity was regained with the same powers as before.

Several pieces of radium were manufactured and sent to scientists in all parts of ihe world. One of these has been received by Professor Langley, of the Smithsonian Institution, America. The specimen had been packed in a small leaden box, with instructions to open it in the dark. A small party at once adjourned to the'photographic dark room, which was of inky blackness. Professor Langley cut the box, and before the astonished scientists could realise what had happened, the room was filled with a clear, greenish glow, bringing out in relief the features of everybody present. At first a few were afraid to touch it, but investigation soon showed that the light was cold and harmless, and that the substance could be picked up with impunity. Immediately after the discovery of radium, Professor Bach of Berlin made tests to ascertain the permanence of the light. He could discover no waste of material whatever, even with his mo3t delicate instruments, and gave as his verdict that it would take a million years to destroy the luminosity of a piece only a quarter of an inch square.